Air Hygiene in Dressing-Rooms for Burns or Major Wounds

The air of operating theatres ventilated by powerful extractor fans was sampled during operations with special media for Cl. welchii and Staph. aureus, and also for total organisms. Counts made with the slit-sampler showed the presence of Cl. welchii in all samples in a range slightly higher than that of Staph. aureus (mostly between five and twenty-five colonies per 100 cu.ft.). There was no evidence of a build-up of either Cl. welchii or Staph. aureus during the course of operations, nor were there any consistent peaks of contamination during operations.Settle plates exposed on numerous days in the operating theatres showed similar counts of Cl. welchii and Staph. aureus—the latter slightly more abundant in this series. Settle-plate counts from many parts of the hospital and from the road outside provided evidence that airborne Cl. welchii comes into the hospital from outside, while Staph. aureus is contributed to the air inside the hospital. This view was supported by study with the slit-sampler and with settle plates in a dressing station ventilated with filtered air, where Cl. welchii was rarely found and Staph. aureus momentarily abundant during dressings; staphylococci but not Cl. welchii were dispersed by the operators in a mock operation. The numbers of airborne Cl. welchii inside and outside the hospital were higher in dry than in rainy weather.Of the patients in the Burns Unit 35% had at some stage Cl. welchii in their burns; contamination was commoner in the more extensive burns. In contrast to Staph. aureus, Cl. welchii was usually present in small numbers and for a short period.Cl. welchii was found in the burns of twenty out of thirty (66%) patients whose rectal swab taken on admission showed the presence of Cl. welchii; a significantly smaller proportion of patients whose rectal swabs were free from Cl. welchii picked up the organism while in hospital (eight out of thirty-two, 25%; x2 = 9.4, P < 0.01). This observation supports the view that burns and possibly other wounds acquire Cl. welchii by self-infection at least as often as from the environment. While it is obvious that plenum ventilation of operating theatres with filtered air is desirable, it is uncertain to what extent this will reduce the small hazard of post-operative gas gangrene.We wish to thank Miss G. Hogg and Mr L. Hurst, F.I.M.L.T. for technical assistance, the surgeons and nursing staff of the Birmingham Accident Hospital for their co-operation, Mr N. R. Gill for photography, and Professors A. A. Miles and C. L. Oakley for kindly sending us strains of Cl. welchii.

mentioning

confidence: 99%

The sources of Hospital infection of wounds with Clostridium welchii

Lowbury

Lilly

1958

“…More recently, a controlled trial (Lowbury, 1954) has shown that Ps. pyocyanea may be excluded from a proportion of burns by the use of an air-conditioned dressing station with filters, previously described by Bourdillon & Colebrook (1946). Cetrimide solution and some other surgical fluids in bottles with cork stoppers have been found contaminated with Ps.…”

mentioning

confidence: 99%

The epidemiology of infection withPseudomonas pyocyaneain a burns unit

Lowbury

Fox

1954

A bacteriological study of burned patients and of the staff and environment in a burns unit was made with the purpose of discovering the principal reservoirs and routes of transfer ofPs. pyocyanea.Infected burns appeared to be the most important reservoirs. About 3 % of the stools of normal subjects and of patients with intestinal symptoms carried the organism, which was also isolated from the nose, throat, nasopharynx, skin and ear of a small proportion of patients and staff in the burns wards.The hands of nurses in the wards were often contaminated withPs. pyocyanea, and presented a likely vector in the transfer of the organism by contact—e.g. from the bandages of infected patients, and from furniture and other objects near to their beds.It was shown by slide agglutination that a new type ofPs. pyocyaneaadmitted to one of the wards spread freely in that ward but hardly at all to the other ward. Since patients from both wards used the same dressing station and operating theatres, it seemed from this finding that a large proportion of the cross-infection occurred in the wards.Polymyxin dusting powder was shown in a controlled trial to protect exposed burns against contamination byPs. pyocyanea.These results are discussed in relation to the mechanism of transfer of the organism and the methods of preventing cross-infection. The need to use several methods concurrently is emphasized, since none of those which have been investigated contributes more than a partial effect. Cubicle wards are advocated, since much cross-infection is shown to occur in open wards.We are much indebted to Dr G. T. Cook for kindly letting us use results obtained by him at the Oxford Public Health Laboratory. We also wish to thank Prof. J. F. D. Shrewsbury of Birmingham University and our colleagues at the Birmingham Accident Hospital for their valuable co-operation, and Dr A. C. Cunliffe of King's College Hospital for information on the typing ofProteusfrom patients in our wards.

“…Quantitative studies on the microbial content of intramural spaces have mainly been performed in public spaces such as hospitals (Bourdillon & Colebrook, 1946;Greene et al 1962), schools (Williams, Lidwell & Hirch, 1956), factories (Favero et al 1966;Hirch, 1951); and a few were done in residential houses (Finch, Prince & Hanksworth, 1978;Scott, Bloomfield & Barlow, 1982). The present study was aimed at the evaluation of the microbial flora of the interior air of an apartment building to determine if it was a threat to public health.…”

Section: Introductionmentioning

confidence: 99%

Microbial investigation of the air in an apartment building

Simard

Trudel

Paquette

et al. 1983

SUMMARYThe microbial and viral flora in the ventilating ducts of an apartment building was evaluated. Several types of sampler (slit sampler, Andersen sampler, large volume air sampler) were used to evaluate the hourly, weekly and seasonal variation of this flora. The mean bacterial concentration was 17-2 c.f.u./m3 with a maximum level at 07.30 h (41-3 c.f.u./m3) and a minimal concentration in the early afternoon (8 c.f.u./m3). The bacterial concentration observed correlated with the relative humidity in the air-ducts although there were no seasonal differences.The bacteria were mainly gram-positive cocci (73-5 %) represented by a large number of Micrococcaceae (47-1 %); gram-positive bacilli accounted for 14-2 % of the isolates, gram-negative bacilli 12-0 % and gram-negative cocci 0-3 %. The majority of the bacteria-carrying particles were in the respirable range with 80-4% of them being less than 5 ,tm. The methods used did not result in the isolation of viruses during the winter sampling period.